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"Experts emphasised that in extreme and catastrophic fire conditions, the surface fuel available for burning makes next to no difference to the level of a fire's intensity.
University of Melbourne associate professor Trent Penman, who studies bushfire behaviour,told Fact Check: "Prescribed burning effectiveness decreases with [increasing] FFDI; when you exceed an FFDI of about 50, you switch from fuel-dominated to a weather-dominated fire.
"At this point, while fuel has a small effect, it is overwhelmed by the weather."
Professor Bradstock agreed, pointing to the example of Victoria's Black Saturday bushfires in 2009 that claimed the lives of 173 people.
His team studied the aftermath of the fires which were associated with an FFDI of well above 100.
They found that even in the areas where fuel had been treated with planned burns less than five years prior, there was no measurable effect on the intensity of the fires.
A Country Fire Authority truck is pictured in front of flames while fighting a Bunyip bushfire
Photo Research has found that the intensity of the Black Saturday bushfires was not mitigated by hazard reduction burning.
AAP: Andrew Brownbill
"At a level where we would have expected the fire intensity to be reduced to suppressible levels, we essentially found no effect," he told Fact Check.
"It's almost like a turbo-charging effect, when you have such incredibly high temperatures and very high winds that you only need a negligible amount of fuel to produce a fire intensity that is not suppressible."
The University of Tasmania's Professor Bowman said that in catastrophic conditions, such as those prevailing in the current Queensland and NSW bushfires, all "organic matter is going to burn".
"There's so much heat and strong winds that the fire is able to travel across landscapes regardless of whether they've been burnt previously. It doesn't affect the [fire] behaviour."